Brown adipose tissue activation is inversely related with central obesity and metabolic parameters in adult human

W. Wang; Q. Wang; M. Zhang; M. Xu; W. Gu; L. Qi; B. Li; G. Ning

Background: Recent studies have shown that adult human possess active brown adipose tissue (BAT), which might be important in affecting obesity and related metabolic risk. However, the supporting evidence in large population based studies is sparse.

Methods: We studied 4011 (2688 males and 1323 females) tumor-free Chinese adults aged 18–89 for BAT activities, visceral/subcutaneous fat areas and metabolic parameters. In vivo 18F-fluorodeoxyglucose (18F-FDG) uptake into adipose tissue and abdominal fat distribution were measured by whole body FDG- positron-emission tomography and computed tomography (PET/CT) and CT scans at umbilicus level.

Results: We found that the prevalence of BAT was around 2.7% in our study participants, with a significant sexual difference (5.5% in the females vs 1.3% in the males; P<0.0001). BAT detection was increased in low temperature and declined in elderly subjects. The BAT positive subjects had lower BMI (P<0.0001), less subcutaneous fat areas (P<0.01), visceral fat areas (P<0.0001), waist circumferences (P<0.0001), lower fasting glucose and triglyceride levels (both P<0.01) and increased HDL cholesterol concentrations (P<0.0001), compared with the BAT negative subjects. Robust logistic regression revealed that after adjustment for covariates (including age, sex, BMI, visceral and subcutaneous fat areas and waist circumferences), age and BMI in the males (OR 0.92 and 0.84, both P<0.008) while age and visceral fat areas in the females (OR 0.87 and 0.98, respectively, P<0.05) were independently associated with detectable BAT.

Conclusion: We found the amount of active BAT is inversely related with central adiposity and metabolic parameters in adult humans, suggesting a potential role of BAT in the control of body weight and metabolic status.

Table 1 The unadjusted and adjusted ORs and 95% CI from the logistic regressions predicting the likelihood of positive BAT
	Male subjects				Female subjects
	unadjusted		adjusted		unadjusted		adjusted
	OR (95% CI)	P	OR (95% CI)	P	OR (95% CI)	P	OR (95% CI)	P
Age (years)	0.90 (0.86–0.94)	<0.0001	0.92 (0.88–0.96)	0.0002	0.87 (0.83–0.89)	<0.0001	0.87 (0.83–0.91)	<0.0001
BMI (kg/m²)	0.80 (0.71–0.90)	0.0003	0.84 (0.75–0.96)	0.008	0.75 (0.67–0.83)	<0.0001	–	–
Waist circumferences (cm)	0.93 (0.90–0.97)	0.0001	–	–	0.93 (0.90–0.97)	<0.0001	–	–
Subcutaneous fat areas (cm²)	0.993 (0.985–1.001)	0.08	–	–	0.989 (0.984–0.994)	<0.0001	–	–
Visceral fat areas (cm²)	0.993 (0.985–1.001)	0.10	–	–	0.96 (0.95–0.98)	<0.0001	0.98 (0.97–0.99)	0.02

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This work was supported, however funding details are unavailable.

Endocrine Abstracts

OC12.5